| This thesis explores nanoimprint lithography (NIL) and its application to organic electronic devices. NIL is a sub-5 nm resolution, high-throughput, low-cost, large-area compatible lithography technology that patterns a polymer film on a substrate by deforming it with a mold.; In Chapter 1, the resolution limits of NIL are investigated; comparing thermalplastic polymer NIL with UV-curable polymer NIL for both the smallest imprint resolution, narrowest pattern pitch, and pattern-transfer capabilities. UV-curable was determined to be superior for all three, with resolution and critical-dimension (CD) control limited by the quality of the mold. Line half-pitch of 20 nm for static random access memory (SRAM) patterns with a line width variation (sigma) of only 1.3 nm were demonstrated. In addition, the ultimate pitch resolution was investigated with a cleaved GaAs molecular beam epitaxy (MBE) mold to demonstrate 6 nm half-pitch line patterning.; In Chapter 2, the fabrication of short-channel polymer organic thin-film transistors (OTFTs) using NIL was used to investigate the device characteristics as the channel length was reduced down to 70 nm. In this study, it was found that the drive current performance increased with a decrease in channel length, while the on/off current ratio remained >104. However the 70 nm channel length devices were current-limited by contact resistance at low, and bulk space-charge effects at high drain voltages respectively.; In Chapter 3, a variety of fabrication methods for gold electrical contacts to single organic molecules were reviewed, and four different schemes were developed that use NIL. A "sandwich" structure was fabricated allowing for the electrical probing of a simple self-assembled monolayer (SAM) of alkanethiol molecules between two gold contacts, in an area as small as 40 x 40 nm2. SAM measurements were performed with repeatable results, but very limited yields and life-times due to the migration of gold atoms from the top contact into the SAM. Three "trap" contact structures were fabricated with contact separation varying from 10 nm down to 2 nm. |
